Oxygen lance arrangement



June 21, 1966 M. PRESTON OXYGEN LANCE ARRANGEMENT 4 Sheets-Sheet 1 Filed June 28, 1963 INVENTOR. MAR T/N PRESTON 4 7'7'0RNEY June 21, 1966 M. PRESTON OXYGEN LANCE ARRANGEMENT 4 Sheets-Sheet 2 Filed June 28, 1965 I NVE NTOR.

MflET/A/ PRESTO/V ww aw TTORNEY June 21, 1966 M. PRESTON 3,257,106

OXYGEN LANCE ARRANGEMENT Filed June 28, 1965 4 Sheets-Sheet 5 E] EI} /'1 6 Fig. 4

INVENTOR M42 7711/ P/QSTU/V ATTORNEY Filed June 28,

June 21, 1966 M. PRESTON OXYGEN LANCE ARRANGEMENT 4 Sheets-Sheet 4 INVENTOR.

M4 7'//\/ PRESTO/v ATraRA/EY United "States Patent 3,257,106 OXYGEN LANCE ARRANGEMENT Martin Preston, Oakland, Calif., assignor to Kaiser Industries Corporation, Oakland, Calif., a corporation of Nevada Filed June 28, 1963, Ser. No. 291,471 7 Claims. (Cl. 266-36) This invention relates to apparatus for the conversion of iron to steel. More particularly, it is concerned with providing a novel arrangement for suspending and manipulating a lance used to introduce oxygen into a vessel used for conversion of iron to steel.

In one process for converting iron to steel, the iron is refined or purified by the use of substantially pure oxygen. A ferrous metalcharge is introduced into a pivotally mounted, refractory-lined conversion vessel or converter. The converter is adapted to be moved from a generally vertical operating or converting position to a tilted pouring or discharging position and vice versa. The conversion vessel is changed through an open mouth with the proper ingredients to form steel after-which'a stream of substantially pure oxygen is directed downwardly onto the surface of the charge to effect the conversion of the charge to steel. The oxygen is introduced through a conduit called a lance which is usually cooled to prevent its destruction, the lance being disposed with-.

in the vessel a suitable distance above the charge.

The conversion process is accompanied by the evolution of hot gases which desirably are carried away from the converter. A suitable flue or duct system is positioned adjacent the mouth of the converter for the purpose of collecting the gases and removing them from the converter when it is in operating position. The flue system usually includes a series of fines that conduct the gases through cooling zones, particle separators, etc., and a hood that is positioned immediately over the mouth of the converter.

During the conversion process the lance extends not only through the mouth of the converter and into the converter but also through an opening in the hood portion of the flue system. Introduction of the lance into and removal of the lance from the converter requires raising the tip of the lance at least as high as the opening in the hood that is provided for receiving the lance.

The overall length of thelance and the distance it must be raised in order to insert it through the hood to a large extent are important factors in determining both the height of the building structure in which the converter is located and the size and. height of the lance handling equipment. Considerable savings in the cost of the structure and lance handling equipment can be realized by minimizing the length of the lance and distance that it-must travel in a vertical direction .to insert or remove it from the converter.

This invention is concerned with providing a novel arrangement for mounting a lance adjacent a converter vessel whereby the overall height of the lance handling equipment and the building structure housing the lance handling equipment and its associated converter vessel can be considerably reduced.

Accordingly, it is a primary purpose of this invention to provide a novel arrangement for suspending and manipulating a lance used in conjunction with steel making converter vessels.

The accompanying drawings are presented to show an apparatus embodying the instant invention and are pre sented as illustrative of the invention rather than limiting in any way upon its scope.

FIG. 1 is a partial sectional elevation of an apparatus embodying thisinvention which is taken along the line 11 of FIG. 3;

FIG. 2 is a view similarto FIG. 1 with various parts of the lance handling equipment being shown in a different position; 1

FIG. 3 is a sectional view of the apparatus shown in FIG. 1 when taken along the line 33 thereof;

FIG. 4 is a partial right side view of the flue assembly shown in FIG. 1;

FIG. 5 is a partial elevation of another apparatus embodying this invention showing in phantom an alternative position of some of the parts thereof; and

FIG. 6 is a partial sectional view of the apparatus shown in FIG. 5 taken along the line 6-6 thereof.

With further reference to the drawings and in particular FIGS. 1-3, the lance handling arrangement of the instant invention is used with a converter 10. Converter 10 consists of the conventional outer metal shell 11, inner refractory lining 12 and trunnions 13 which pivotally support the converter. Converter 10 has an open mouth 15 and when supported by its trunnions 13, it is capable of being moved or tilted from the vertical position shown in the drawings to a horizontal position in which the contents 16 can be discharged through the open mouth 15. V I

'When the vessel 10 is in its normal vertical or converting position, the mouth 15 is aligned with a gas collecting hood portion 17 of a flue system. The hood 17 ordinarily will have double walls such as an outer wall 18, an inner wall 20 and a cooling fluid receiving space 21 between the Walls 18 and 20. Conduit means 22 is connected for supplying cooling fluid to the space 21 between the walls thereby preventing heat damage to the hood.

One side of the hood 17 is provided with a vertically elongated opening or slot 23. The lower extremity of slot 23 is shown intercepting the bottom edge 25 of the hood. Slot 23 can best be seen in FIG. 4 where the hood 17 is shown without the lance assembly installed. Slot 23 serves as an access opening in the hood 17 for introducing an oxygen supply lance 26 through the hood into the converter 10 and above the charge 16.

In one embodiment of the invention the lance employed is L-shaped, i.e., the lance has a generally vertically disposed portion 28 and another portion 27 disposed or oriented at an angle thereto.

Leg portion 28 of the lance 26 terminates in a nozzle or opening 30 through which oxygen is discharged against the surface of the charge 16. Leg portion 27 of the lance terminates in a header 31 through which oxygen is supplied to the lance by Way of line 32. Lines 33 and 35 afiixed to header 31 are used to introduce cooling fluid to and remove such fluid from the lance in a mannerconventional in the art. For this purpose the lance 26 is usually constructed of concentric tubes, the inner one of which provides for the passage of oxygen and the annular space between the tubes being employed to circulate cooling fluid. Slidably disposed with respect to hood 17 is a cover member 36. Leg 27 of thelance as well as header 31 are aflixed to cover member 36 in such a fashion that when the lance is in its operative position within vessel 16, the slot 23 is substantially completely.

covered by the cover member 36. Cover member 36 is held tightly against the opening 23 by suitable clips 37 aflixed to the hood 17. A steel cable 38 or the like reeved over pulley 40 can be advantageously employed to lower and raise the cover member 36 into and out of alignment with slot 23. Cover 36 is provided with a have a separate conventional connection to receive cooling fluid.

To operate the device illustrated in FIGS. 1-3, the converter is tilted on its trunnions l3 and charged with molten iron, solid scrap and various slag-forming ingredients that are required for producing steel from the ferrous charge. When charging is complete, the converter 10 is rotated to its vertical converting position with open mouth beneath the hood 17. During charging the oxygen lance is in the position shown in phantom in FIG. 2, but after charging the lance is rotated around pivot 41 so that the leg 28 passes through the slot or elongated opening 23 to a position within the walls of the hood 17. The lance is then lowered from the position shown in solid lines in FIG. 2 to the operating position shown in FIG. 1. In moving to the position shown in FIG. 1, the cover 36 first moves so that it is snugly against outside wall 18 of the hood, and then it moves downwardly and is engaged by clips 37 which hold it firmly against the opening 23. Thus, when the lance is in operating position, the slot 23 is sealed by the cover 36 so that there will be substantially no passage of gas through slot 23.

Conversion reactions are initiated by passing oxygen through line 32, then passing it through leg 27 and then leg 28 and ultimately out of opening 30 of the lance. Before initiating the reactions cooling water flow through lines 33 and 22 is started and the cooling water is withdrawn through lines 35 and 42. The conversion reactions result in the evolution of a large volume of hot gases which pass through the hood 17. Upon the com- I pletion of the conversion reactions, the molten material within the converter 10 includes finished steel product, which is discharged from the converter by tipping it to pour from the open mouth 15. Before this can be accomplished, however, the lance leg 28 must be withdrawn from the converter and this is accomplished by exerting force on cable 38 to raise the lance assembly 26 into the position shown in solid in FIG. 2. In this position, the converter 10 can be discharged.

If it is desirable to do maintenance work on the lance, the lance assembly 26 may be moved into the position shown in phantom in FIG. 2 in which position both legs of the lance and all surfaces of the slot cover 36 are available for maintenance. In the operation of the apparatus as described herein, it may be noted that it is not necessary to raise the lance higher than leg 28 extends into converter 10 in order to discharge the converter or to withdraw the lance from the converter or the hood. Process and apparatus considerations other than the length of the lance or the means for manipulating it determine the height of the structure and equipment employed in the process, and the compact and efficient mode of handling the lance that is the subject of this invention permits it to be substantially shorter than the straight, vertical lances heretofore employed, easily and quickly inserted and withdrawn from the converter 10 and readily available for maintenance and inspection when not in use. Furthermore, the L-shaped lance of this invention permits the use of a vertical hood 17 since the lance does not have to pass vertically through the hood and into the converter.

FIGS. 5 and 6 are fragmentary views illustrating another hood employing the present invention. In FIGS. 5 and 6 the hood generally designated as 43 is constructed with three vertical sides and one sloping side 45. Although not shown, the hood 43 may be constructed with double walls and means for introducing cooling fluid between the Walls as described hereinabove. The sloping side 45 is provided with an opening or slot 46 that is axial with side 45 and positioned to permit the vertical portion of a lance to pass through it. Hinges 47 connect a slot cover 48 to the side 45 so that the cover superimposes all, except the lowermost portion, of the slot 46. The uncovered portion 50 of the slot 46 is at least as large as the cross-section of the lance.

As in the other embodiments, the lance 51 consists of a horizontal leg 52 and a vertical leg 53. At one end there is a header 55 adapted as hereinbefore described with inlets and outlets for cooling fluid and oxygen which are not shown, and at the other end there is an opening 56 to discharge oxygen.

In operation during the charging of a converter, the lance assembly 51 will be in the position shown in phantom in FIG. 5. After the converter is charged and it is desired to begin conversion reactions, the cover 48 is raised and the lance assembly is moved horizontally through the slot 46 sothat the vertical leg of the lance 53 is within the confines of hood 43. The lance assembly is then lowered into the position shown in solid in FIGS. 5 and 6, and when the desired operating position of the lance is reached, the slot cover 48 will close to cover the slot except for the small portion occupied by the lance. Conversion may then be begun because the lance is positioned above the charge in the converter and the hood 43 is in gas collecting position with respect to the converter and with slot 46 covered.

From the foregoing description it is evident that this invention provides a novel lance and vent assembly that diminishes substantially the problems of operation and the equipment necessary for operating an oxygen conversion process.

It is also evident that many modifications may be made within the scope of this invention which include but are not limited to the use of hoods that may be sealed with respect to the converter, the use of inert or other gas curtains to seal the slots in the hood through which the lance passes, the use of various hoists, rails, brakes, etc., to raise and lower the lance assembly or to move it into or out of the hood, to mention but a few.

What is claimed is:

1. An apparatus for oxygen conversion of iron to steel which comprises a conversion vessel pivotally mounted to be movable from a normal converting position to a tilted pouring position, a mouth in said vessel opening upwardly when said vessel is in normal converting position, a hood in gas collecting position with respect to said mouth when said vessel is in normal converting position, means in said hood defining an elongated opening through said hood, an L-shaped lance including a first leg, a second leg that is not axial with said first leg, means for introducing gas into said first leg and an opening to discharge said gas from said second leg, said elongated opening in said hood being wider than'the major crosssection dimension of said lance and long enough for said second leg to pass through it, means for moving said lance between upper and lower positions, means for moving said second leg through said elongated opening between a position with said second leg enclosed within said hood and a position with said second leg outside of said hood and means for sealing said elongated opening when said second leg is in said lower position and enclosed within said hood.

2. The apparatus of claim 1 further characterized in that said means for sealing said elongated opening comprises an elongated panel connected to slide in the direction of elongation of said opening.

3. The apparatus of claim 1 further characterized in that said means for sealing said elongated opening comprises a panel connected to said first leg, said panel being elongated in the direction of elongation of said opening and being substantially the length of said opening.

4. The apparatus of claim 2 further characterized in that said hood and said means for sealing said elongated opening are constructed with spaced double walls and are provided with means for introducing and for withdrawing cooling fluid from the space between said double walls.

5. The apparatus of claim 1 further characterized in that said means for sealing said elongated opening comprises a panel mounted to rotate about an edge of said panel on an axis that is perpendicular to the longitudinal axis of said elongated opening.

6. The apparatus of claim 2 further characterized in that said panel is linearly movable with respect to said hood in the direction of elongation of said elongated opening and pivotally movable around a horizontal axis.

7. The apparatus of claim 1 further characterized in that said means for sealing said elongated opening comprises a cover extending from the top of said opening to a distance above the bottom of said opening, said distance being at least equal to the major cross-section dimension of said lance, and said cover further being mounted to rotate about an edge of said cover that is parallel with a longitudinal axis of said elongated opening.

References Cited by the Examiner FOREIGN PATENTS 218,553 12/1961 Australia.

WHITMORE A. WILTZ, Primary Examiner.

O M. L. FAIGUS, Assistant Examiner. 

1. AN APPARATUS FOR OXYGEN CONVERSION OF IRON TO STEEL WHICH COMPRISES A CONVERSION VESSEL PIVOTALLY MOUNTED TO BE MOVABLE FROM A NORMAL CONVERTING POSITION TO A TILTED POURING POSITION, A MOUTH IN SAID VESSEL OPENING UPWARDLY WHEN SAID VESSEL IS IN NORMAL CONVERTING POSITION, A HOOD IN GAS COLLECTING POSITION WITH RESPECT TO SAID MOUTH WHEN SAID VESSEL IS IN NORMAL CONVERTING POSITION, MEANS IN SAID HOOD DEFINING AN ELONGATED OPENING THROUGH SAID HOOD, AN L-SHAPED LANCE INCLUDING A FIRST LEG, A SECOND LEG THAT IS NOT AXIAL WITH SAID FIRST LEG, MEANS FOR INTRODUCING GAS INTO SAID FIRST LEG AND AN OPENING TO DISCHARGE SAID GAS FROM SAID SECOND LEG, SAID ELONGATED OPENING IN SAID HOOD BEING WIDER THAN THE MAJOR CROSSSECTION DIMENSION OF SAID LANCE AND LONG ENOUGH FOR SAID SECOND LEG TO PASS THROUGH IT, MEANS FOR MOVING SAID LANCE BETWEEN UPPER AND LOWER POSITIONS, MEANS FOR MOVING SAID SECOND LEG THROUGH SAID ELONGATED OPENING BETWEEN A POSITION WITH SAID SECOND LEG ENCLOSED WITHIN SAID HOOD AND A POSITION WITH SAID SECOND LEG OUTSIDE OF SAID HOOD AND MEANS FOR SEALING SAID ELONGATED OPENING WHEN SAID SECOND LEG IS IN SAID LOWER POSITION AND ENCLOSED WITHIN SAID HOOD. 